JP2004213988A - Static eliminator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a static eliminator capable of adjusting jet force of an airflow carrying ions while restraining barometric variation in an ion generation part. <P>SOLUTION: In order to reduce jet force of a first airflow L1 from a nozzle 50, the nozzle 50 and a ventilation member 60 are extracted from a head part 13, another ventilation member 60 having first ventilation holes 66 more than those of it is plunged into a housing part 32, and the nozzle 50 is mounted on the head part 13. Therefore, a passage cross-sectional area of the airflow L1 for carrying ions is increased, and its flow velocity is reduced, so that the jet force of the airflow L1 from the nozzle 50 can be reduced. On the contrary, in order to increase the jet force of the nozzle 50, the passage cross-sectional area of the airflow L1 for carrying ions is reduced by replacing the ventilation member with another ventilation member 60 having the ventilation holes 66 less than those of it, and its flow velocity is increased, so that the jet force of the airflow L1 from the nozzle 50 can be increased. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a static eliminator that supplies air from an air supply port into an ion generation unit to generate an air flow, and discharges ions generated in the ion generation unit from a discharge port to the outside.
[0002]
[Prior art]
Conventionally, as this type of static eliminator, there is one disclosed in Patent Literature 1 below. This is to generate ions by a corona discharge generated by applying an AC high voltage between a discharge needle disposed in an ion generation chamber having an air supply port and an air discharge port and a ground electrode, By feeding air from the mouth, the ions are guided to the air discharge port side, and are blown to the object to be neutralized through the injection tube connected to the air discharge port.
[0003]
[Patent Document 1]
JP 2000-138090 A
[Problems to be solved by the invention]
By the way, the object of static elimination includes a minute and light object (a minute object) such as a precision part, and an object to be neutralized over a relatively large area such as a printed circuit board (a large object). ). For a small object, if the jet velocity of the air flow from the ejection tube is too high, the minute object itself may be blown off by the force, and it is necessary to weaken the jet force of the air flow from the ejection tube. is there. On the other hand, for a large object, the spray tube is sprayed from a position somewhat away to remove electricity from a wide area. In this case, the air is blown so that sufficient ions are blown to the separated large object. The jet force of the stream needs to be relatively strong. However, in the conventional static eliminator, there is a problem that the jet force of the air flow from the jet tube cannot be changed at a constant level, and appropriate static elimination cannot be performed according to the target of static elimination.
[0005]
In addition, a method of adjusting the injection force of the air flow from the injection tube by changing the supply amount (supply pressure) of the air supply means for sending air from the air supply port can be considered, but this method is as follows. Problems arise. That is, when the supply amount by the air supply unit is changed, the air pressure in the ion generation unit also changes. Here, the voltage required for generating corona discharge (discharge start voltage level) is substantially proportional to the atmospheric pressure. Therefore, the discharge start voltage level increases with the fluctuation of the atmospheric pressure in the ion generation chamber, and corona discharge becomes unstable. It will be.
[0006]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a static eliminator capable of adjusting the injection force of an air flow carrying ions while suppressing pressure fluctuations in an ion generator. There.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, in the static eliminator according to the first aspect of the present invention, ions generated in the ion generator by applying a voltage to the discharge needle to cause corona discharge are arranged at one end of the ion generator. In a static eliminator that discharges the air from the discharge port formed to communicate with the other end of the ion generation section to the outside by being put on the air flow sent from the air supply port, the discharge is performed from the discharge port through the ion generation section from the air supply port. It is characterized in that a flow rate adjusting means for changing the flow rate is provided in the flow path of the air flow.
[0008]
According to a second aspect of the present invention, in the static eliminator according to the first aspect, the flow rate adjusting means arranges a ventilation member having a ventilation hole so as to block a flow path of the air flow, and the ventilation holes have different opening areas. It is characterized by being configured to be replaceable with a ventilation member.
[0009]
According to a third aspect of the present invention, in the static eliminator according to the second aspect, the discharge port is formed to have substantially the same diameter as an opening diameter of the ion generation section communicating with the discharge port, and a wall of the ion generation section opposite to the discharge port. An insertion hole through which the discharge needle can be inserted from the outside is formed in the part, and the discharge needle is detachably attached to the insertion hole with its tip side protruding into the ion generation part, and in a sealed state. Inserted, the ventilation member is provided with a through hole through which at least the needle tip portion of the discharge needle can be inserted, and is characterized in that it is provided in a state where the distal end side of the discharge needle is inserted into the through hole in the ion generation unit. Have.
[0010]
Function and effect of the present invention
<Invention of claim 1>
According to this configuration, the flow velocity of the air flow discharged from the discharge port through the ion generation section from the air supply port can be changed by the flow velocity adjusting means. Thus, the ejection force from the discharge port can be adjusted according to the charge removal target (for example, the size of the charge removal target, the range of the charge removal range, etc.). In addition, since the supply amount of the air supply means is not changed as described in the related art, fluctuations in the atmospheric pressure in the ion generation unit can be suppressed, and static electricity can be removed by stable corona discharge.
[0011]
<Invention of Claim 2>
ADVANTAGE OF THE INVENTION According to this invention, the ventilation member provided with the ventilation hole which the airflow can pass is interposed in the flow path (for example, in an ion generation part) of the airflow which passes through an ion generation part from an air supply port, and a discharge opening. The ventilation member can be replaced with another ventilation member having a different opening area of the ventilation hole. Therefore, only by changing the ventilation member, it is possible to adjust the flow rate of the airflow from the discharge port and, consequently, the injection force thereof in accordance with the object to be neutralized.
[0012]
<Invention of Claim 3>
For example, when the discharge port is smaller in diameter than the ion generation unit, there is a possibility that the air pressure in the ion generation unit may increase due to the pipe resistance in the discharge port against the air flow. Therefore, according to the present configuration, the discharge port is formed to have substantially the same diameter as the ion generation unit, so that the pressure increase in the ion generation unit can be suppressed as compared with the ion generation unit having a smaller diameter. Further, the discharge needle is detachably held from an insertion hole formed through a wall of the ion generating portion opposite to the discharge port, and the ventilation member is disposed on the tip side of the discharge needle. It has become. Therefore, for example, when the discharge needle has deteriorated, the discharge needle can be replaced while the ventilation member is held on the ion generation unit side, and the replacement work can be facilitated.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
One embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, a resin-made main body case 11 that forms a housing of the static eliminator 10 has a block-shaped head portion 13 integrally formed on an upper surface on one end side of a box-shaped substrate housing portion 12 having an open bottom surface. It becomes. Hereinafter, the side on which the head section 13 is provided (the left side in FIG. 1) will be described as the front.
[0014]
The board accommodating section 12 is closed by a lid section 15 in a state in which the printed wiring board 14 is accommodated, and a high voltage generating circuit section 16 is mounted on the printed wiring board 14 and a cable 17 is connected thereto. The cable 17 is led out in a fixed state by a cable holder 18 provided at the rear end of the main body case 11. A plurality of LEDs (not shown) indicating the operation state of the static eliminator 10 are mounted on the printed wiring board 14, and the LEDs are connected to the outside through a window 19 originally formed on the upper surface of the rear end of the case. (See FIG. 2). A pair of mounting portions 20 having mounting holes are provided at diagonal positions of the substrate accommodating portion 12, and mounting screws are passed through the mounting holes of the pair of mounting portions 20 and 20 to predetermined mounting locations. The static elimination device 10 is fixedly arranged by screwing.
[0015]
As shown in FIG. 2, the head portion 13 is open only on the rear end side, and has an air supply portion 21 to which an air tube holder 23 described below is mounted, and a cavity formed to penetrate in the front-rear direction from the front end to the rear end. And a cylindrical ion generating section 30 having a section. An opening end side of the air supply unit 21 is a mounting hole 24 in which an air tube holder 23 connected to a tip of an air tube 22 connected to an air supply unit (not shown) is mounted.
[0016]
On the other hand, the front end side of the hollow portion of the ion generation unit 30 is a nozzle mounting hole 31 for mounting a metal nozzle 50 (corresponding to the “discharge port” of the present invention) functioning as a ground electrode, A thread groove is cut in the inner peripheral surface. A central portion in the front-rear direction of the hollow portion communicates with the nozzle mounting hole 31 with substantially the same diameter, and a housing portion 32 in which a ventilation member 60 described later is disposed. An air intake section 33 connected to the mounting hole 24 of the air supply section 21 is formed continuously. The rear end side of the hollow portion has a smaller diameter than the air intake portion 33 and serves as a unit insertion hole 34 (corresponding to the “insertion hole” of the present invention) into which the discharge needle unit 40 described below is inserted. ing. A nut insertion hole 34A is formed through the lower surface of the front end side of the unit insertion hole 34 so as to reach the back side of the board housing portion 12, so that a nut member 35 described later can be inserted therefrom.
[0017]
Next, the discharge needle unit 40 includes a discharge needle 41, a metal discharge needle holding portion 42 that holds the base end portion of the discharge needle 41 so that the tip is broken in the axial direction and is sandwiched between the splits, and the discharge needle 41. The knob unit 43 is integrally formed so as to cover the base end portion of the needle holding unit 42, and is provided with a knurl R for preventing slip on the outer peripheral surface on the rear end side. A constricted portion 42A having a smaller diameter than other portions is formed at a central portion in the axial direction of the discharge needle holding portion 42 so that the O-ring 44 can be attached thereto. A groove 42B is formed.
[0018]
The nut member 35 inserted from the back side of the substrate accommodating portion 12 through the nut insertion hole 34A is a conductive plate-shaped member, and the discharge needle unit 40 is provided in an inner surface of a hole 35A formed substantially at the center thereof. The screw groove is cut so as to screw with the screw groove 42B formed in the discharge needle holding portion 42 of FIG. As shown in FIG. 2, the nut member 35 is inserted into the nut insertion hole 34A until the hole 35A becomes coaxial with the unit insertion hole 34, and the O-ring 44 is attached to the constricted portion 42A. The knob portion 43 is rotated while inserting the discharged needle unit 40 into the unit insertion hole 34 from behind, and screwed into the nut member 35. With such a configuration, the discharge needle unit 40 can be attached to and detached from the head portion 13, and the O-ring 44 is pressed against the constricted portion 42 </ b> A and the inner peripheral surface of the unit insertion hole 34 to seal the discharge needle unit 40. It is kept in a state.
[0019]
Next, the nozzle 50 has a cylindrical shape as a whole, and its central portion in the axial direction is larger in diameter than other portions. On the outer peripheral surface on the rear end side of the nozzle 50, a constricted portion 52 for ringing the O-ring 51 is formed and a thread groove is cut, while the inner peripheral surface of the nozzle mounting hole 31 of the head portion 13 is formed. Also, the thread groove is also cut, whereby the nozzle 50 is detachably attached to the head portion 13 and is held in a sealed state. The hollow portion 53 of the nozzle 50 has a large diameter at the rear from a substantially central position in the axial direction, and the insulating tube 54 is mounted here with the rear end portion protruding rearward. . Note that the inner surface of the insulating tube 54 mounted in the hollow portion 53 is flush with the inner wall surface of the front portion from the central position of the hollow portion 53. In the nozzle 50, four micro holes 55 are formed so as to surround the hollow portion 53 along the axial direction.
The nozzle 50 and the nut member 35 described above are electrically connected to the printed wiring board 14, and a high voltage is applied between the nozzle 50 and the nut member 35 by the high voltage generation circuit unit 16 mounted thereon. As a result, corona discharge is generated at the tip of the discharge needle 41 electrically connected to the nut member 35 to generate ions.
[0020]
By the way, in the present embodiment, a plurality of types of ventilation members 60 arranged in the accommodation portion 32 communicating with the rear of the nozzle mounting hole 31 are prepared. Each of the ventilation members 60 has a disk shape corresponding to the cross-sectional shape of the housing portion 32 as a whole, and annular walls 61 protruding in the axial direction are formed at respective peripheral edges on both surfaces thereof. A protruding portion 62 having a circular cross section corresponding to the inner diameter of the insulating tube 54 is formed at a central portion of a surface (hereinafter, “front surface”) facing the rear end surface of the nozzle 50 in the portion 32. Then, as shown in FIGS. 3A and 3B, the ventilation member 60 is formed with a discharge needle through-hole 63 penetrating from the tip of the projection 62 to the rear surface through the center axis thereof, and the projection 62 A pair of second ventilation holes 65, 65 extending from the bottom surface to the rear surface of the concave portion 64 between the annular wall portion 61 and the protruding portion 62 are formed at symmetrical positions with respect to.
[0021]
Here, the ventilation member 60 is formed with a first ventilation hole 66 (corresponding to a “vent hole” of the present invention) formed around the discharge needle penetration hole 63 so as to extend from the tip of the projection 62 to the rear surface. The number of the first ventilation holes 66 differs depending on the ventilation member 60. FIGS. 3 (A) and 3 (B) show one of them. In this ventilation member 60, three first ventilation holes 66 are formed along the circumferential direction so as to surround the discharge needle through hole 63. The through holes are formed so as to be arranged at intervals. Although not shown, the first ventilation holes 66 are formed in the other ventilation members 60, for example, in one, two, four, five,. . . It is formed through. The first ventilation holes 66 are tapered surfaces that increase in diameter from the base end of the protrusion 62 toward the rear surface.
[0022]
A ridge 32 </ b> A is formed on the inner surface of the housing portion 32 along the circumferential direction thereof, while a locking groove 67 is formed on the outer circumferential surface of each ventilation member 60 along the circumferential direction. Locked. In order to mount the ventilation member 60 in the accommodating portion 32, as shown in FIG. 4, the ventilation member 60 is pushed inward (rearward) while the tip of the discharge needle 41 is inserted into the discharge needle through hole 63. Then, by fitting the ridge 32A of the housing portion 32 into the locking groove 67, the ventilation member 60 is temporarily held in the housing portion 32. Subsequently, the insulating tube 54 is mounted on the nozzle 50, and the nozzle 50 is screwed into the nozzle mounting hole 31 of the head unit 13. As a result, the ventilation member 60 has its protruding portion 62 fitted into the rear end of the insulating tube 54, and the upper end surface of the front annular wall portion 61 abuts on the rear end surface of the nozzle 50. It is fixed to the part 32.
[0023]
With the above configuration, part of the air sent from the air supply unit 21 into the air intake unit 33 passes through the first ventilation hole 66 of the ventilation member 60, and passes through the insulating tube 54 and the through hole of the nozzle 50. (Hereinafter, this air flow is referred to as “first air flow L1”). The other air passes through the second ventilation holes 65 of the ventilation member 60 and enters the annular space formed between the rear end face of the nozzle 50 and the concave portion 64 of the ventilation member 60, and communicates with the annular space. The air is discharged to the outside through the four minute holes 55 of the nozzle 50 (hereinafter, this air flow is referred to as a “second air flow L2”). Therefore, the ions generated at the tip of the discharge needle 41 by the corona discharge are jetted to the outside on the first air flow L1.
[0024]
Then, in order to weaken the jetting force of the first airflow L1 from the nozzle 50 in a state where the ventilation member 60 having three first ventilation holes 66 is provided, the nozzle 50 is detached from the head portion 13. Then, the ventilation member 60 is taken out, another ventilation member 60 having a larger number of first ventilation holes 66 is pushed into the housing portion 32, and the nozzle 50 is mounted on the head portion 13 again. Thereby, the flow velocity of the first air flow L1 on which the ions are loaded increases, and the flow velocity decreases, so that the jet force of the first air flow L1 from the nozzle 50 can be weakened.
On the other hand, in order to increase the ejection force of the first airflow L1 from the nozzle 50 in a state where the ventilation member 60 having three first ventilation holes 66 is provided, the nozzle 50 is also moved from the head portion 13. Then, the ventilation member 60 is taken out, another ventilation member 60 having a smaller number of first ventilation holes 66 is pushed into the housing portion 32, and the nozzle 50 is mounted on the head portion 13 again. Thereby, the flow velocity of the first air flow L1 on which the ions are loaded is reduced, and the flow velocity is increased, so that the ejection force of the first air flow L1 from the nozzle 50 can be increased.
[0025]
As described above, according to the present embodiment, by selectively exchanging the plurality of ventilation members 60 having the same number of first ventilation holes 66 having different diameters, the object to be neutralized (for example, the size of the object to be neutralized, the static elimination is performed). The power of the first air flow L1 carrying the ions from the nozzle 50 can be adjusted according to the width of the power range. In addition, since the supply amount of the air supply means is not changed as described in the conventional description, static electricity removal by stable corona discharge can be performed while suppressing pressure fluctuation in the ion generation unit 30.
Further, when the discharge needle 41 is deteriorated, the discharge needle unit 40 can be removed and replaced from the unit insertion hole 34 at the rear end of the ion generator 30, so that the discharge can be easily performed without removing the nozzle 50 and the ventilation member 60. The replacement work of the needle 41 can be performed.
Further, the inner diameter of the insulating tube 54 arranged so as to surround the tip of the discharge needle 41 is configured to be the same as the inner diameter of the nozzle 50 in front thereof, so that the tip end side of the nozzle 50 becomes smaller in diameter. The pressure rise in the insulating tube 54 can be suppressed as compared with the case where the pressure is higher.
In the present embodiment, the nozzle 50 is provided with the fine holes 55 so that the nozzle 50 is provided with the first air flow L1 carrying the ions in a direction substantially parallel to the discharge direction of the first air flow L1. To discharge the second airflow L2. The first airflow L1 carrying the ions is drawn into the second airflow L2, and the ions are discharged far away by multiplying the first airflow L1, whereby it is possible to perform a wide range of static elimination on the static elimination target.
[0026]
<Other embodiments>
The present invention is not limited to the above-described embodiments. For example, the following embodiments are also included in the technical scope of the present invention, and furthermore, various embodiments may be made without departing from the spirit of the present invention. It can be changed and implemented.
(1) In the above embodiment, the ventilation member 60 and the discharge needle 41 are formed separately, but may be formed integrally. However, with the configuration as in the above-described embodiment, there is a merit that, when exchanging the ventilation member 60 and the discharge needle 41, one can be exchanged without removing one.
[0027]
(2) In the above embodiment, the first air holes 66 have the same diameter. However, the present invention is not limited to this. For example, the first air holes 66 may have different diameters. Further, the cross-sectional shape of the first insertion hole does not necessarily have to be round, but may be triangular, quadrangular, or the like. Further, a gap formed by making the diameter of the discharge needle through hole 63 larger than the outer diameter of the discharge needle 41 without providing the first air hole 66 may be referred to as a “vent hole” in the present invention.
[0028]
(3) Further, in the above-described embodiment, the first ventilation holes 66 have the same diameter and differ in the number between the plurality of ventilation members 60, but are not limited thereto. May be the same or different in diameter. In short, it is only necessary that the total opening area of the first ventilation holes 66 differs between the ventilation members 60.
[0029]
(4) In the above embodiment, the ventilation member 60 is arranged around the tip of the discharge needle 41. However, the present invention is not limited to this. For example, the ventilation member 60 may be arranged in front of the discharge needle 41.
[0030]
(5) As the "flow rate adjusting means" in the present invention, for example, there are the following configurations (a, b).
a. As in the above embodiment, the nozzle 50 is detachable from the head portion 13 and the flow rate of the airflow from the nozzle tip is adjusted by replacing the hollow portion 53 with another nozzle having a different diameter.
b. As shown in the schematic diagram of FIG. 5, a wall portion 71 is provided so as to overlap the front surface or the rear surface of the ventilation member 70, a through hole 71A is formed at a predetermined position of the wall portion 71, and the ventilation member 70 is positioned at the center thereof. A configuration in which the overlapping area between the through hole 71A of the wall portion 71 and the ventilation hole 70A of the ventilation member 70 is changed by rotating about the axis. With such a configuration, the flow rate of the airflow can be changed by one type of ventilation member 70, and an increase in the number of parts can be suppressed. When the wall 71 is arranged on the front surface of the ventilation member 70, the wall 71 and the discharge port (nozzle) may be integrally formed.
[Brief description of the drawings]
1 is a sectional view of a static eliminator according to an embodiment of the present invention; FIG. 2 is a plan sectional view thereof; FIG. 3 is a front view and a rear view of a ventilation member. FIG. 5 is a perspective view showing the fitting relationship of FIG. 5; FIG.
DESCRIPTION OF SYMBOLS 10 ... Static eliminator 21 ... Air supply part 30 ... Ion generation part 31 ... Nozzle mounting hole 32 ... Housing part 33 ... Air intake part 34 ... Unit insertion hole 35 ... Nut member 41 ... Discharge needle 44 ... O-ring 50 ... Nozzle ( Outlet)
53 hollow part 54 insulating tubes 60 and 70 ventilation member 63 discharge needle through hole 66 first ventilation hole 70A ventilation hole 71 wall 71A through hole L1 first air flow

Claims (3)

By applying a voltage to the discharge needle to cause corona discharge, ions generated in the ion generator are placed on an air flow sent from an air supply port arranged on one end side of the ion generator, and the ions are generated by the ion generator. In a static eliminator that discharges outside from a discharge port formed to communicate with the other end side,
A static eliminator, wherein a flow rate adjusting means for changing a flow rate of the air flow discharged from the discharge port through the ion generating section from the air supply port is provided. The flow rate adjusting means is configured by arranging a ventilation member having a ventilation hole in a flow path of the airflow, so that the ventilation member can be replaced with a ventilation member having a different opening area of the ventilation hole. The static eliminator according to claim 1. The emission port is formed to have substantially the same diameter as the opening diameter of the ion generation unit communicating therewith,
An insertion hole through which the discharge needle can be inserted from the outside is formed in a wall portion of the ion generation section opposite to the emission port, and the discharge needle has its tip side inserted into the ion generation section. Detachable to the insertion hole in a protruded state, and inserted in a sealed state,
The ventilation member is provided with a through hole through which at least a needle tip of the discharge needle can be inserted, and is provided in a state where the tip side of the discharge needle is inserted into the through hole in the ion generating unit. The static eliminator according to claim 2, characterized in that:

Images